Increasing the efficiency of internal combustion engines is critical to meet customer expectations and to meet an array of government-mandated regulations. Internal combustion engines generate significant amounts of heat that heat exchangers eventually transfer to the air surrounding the internal combustion engine. If a portion of the wasted heat were recovered by performing a necessary engine function, the efficiency of the internal combustion engine would be improved. However, there remain opportunities for improving the use of waste heat. For example, heat may be recovered directly from an engine body and/or cylinder head rather than indirectly. Such a system may require improvements in the ability to select the best source of heat to optimize heating and cooling throughout the systems of an internal combustion engine.